Usability of the Ranibizumab 0.5 mg Prefilled Syringe: Human Factors Studies to Evaluate Critical Task Completion by Healthcare Professionals

Purpose: A ranibizumab prefilled syringe (PFS) has been approved by the U.S. Food and Drug Administration. Here we evaluate the use of the ranibizumab PFS for intravitreal injection by assessing whether the PFS enables healthcare providers to successfully prepare and administer an injection without prior training.

Design: Simulated-use and actual-use human factors usability studies.

Participants: Retina specialists and ophthalmic medical personnel.

Methods: In a simulated-use summative usability study, retina specialists (n = 15) and ophthalmic medical personnel (n = 15) prepared the ranibizumab PFS and performed injections into a model eye. In an actual-use formative usability study (ClinicalTrials.gov identifier: NCT02698566), three assistants and three retina specialists prepared the PFS and performed intravitreal injections, respectively, in study eyes of patients with retinal diseases (n = 35).

Main Outcome Measures: Twelve tasks specific to the unpacking, preparing, and properly administering the PFS for intravitreal injection were evaluated by a study assessor. Task performances were evaluated for use errors, close calls, and operational difficulties. Post-injection subjective user evaluations were performed to assess ease of use.

Results: All participants successfully performed all essential and safety-critical tasks without use error in both the simulated-use and actual-use human factors usability studies. The majority of participants rated the tasks required to use the ranibizumab PFS as “Easy” or “Very Easy.”

Conclusions: Both the simulated-use and actual-use usability studies yielded consistent data, showing that healthcare professionals are able to use the ranibizumab PFS by successfully performing all critical tasks involved in preparing and delivering an intravitreal injection. The simulated-use usability testing was sufficiently realistic and representative of real-world use, and was appropriate and preferred over actual-use usability testing for proper evaluation of the product user interface.

LAY ABSTRACT: Ranibizumab is approved in the United States to treat various eye conditions, including neovascular (wet) age-related macular degeneration, macular edema following retinal vein occlusion, diabetic macular edema, diabetic retinopathy, and myopic choroidal neovascularization. It is administered as an injection into the eye once a month, and is available in a vial from which medication needs to be withdrawn using a standard syringe with a 19-gauge filter needle. The filter needle is then replaced by a smaller gauge needle for the intravitreal injection. The recent U.S. Food and Drug Administration approval of a 0.5 mg ranibizumab prefilled syringe eliminates the need for withdrawing medication from a vial and changing needles prior to use. The studies described in this report assessed the usability of the ranibizumab prefilled syringe by retina specialists and ophthalmic medical personnel in simulated- and actual-use settings. Twelve tasks that included unpacking, preparing, and properly administering the prefilled syringe for intravitreal injection were evaluated by a study assessor. Task performances were evaluated for use errors, close calls, and operational difficulties. Participants successfully performed all the tasks without any critical errors in both simulated-use and actual-use human factors usability studies, and most participants found the syringe to be “Easy” or “Very Easy” to use.